HSI failure in flight

[GMascelli]

Posting for a friend who just experienced this problem....

For those you fly an HSI who had a failure in flight, how did the HSI die?


His experience was HDG flag flicker intermittently for 5-10 min then no heading flag for 10 minutes, followed by a solid HDG flag, heading not rotating with aircraft bank, HSI dead.... then 30 sec latter a strong smell consistent with an electrical burn filled the cockpit. Aircraft is a C172 2001 S model. The HSI is the KI-55A slaved system.

The reason he is asking is some are thinking this a broader electrical issue, and want to have feelers on what to expect for the possible flight to a repair shop.

 

[Rob Schaffer]

Not taking it to Red Eagle I suppose?

 

[GMascelli]

Not taking it to Red Eagle I suppose?

LOL.....beats me! I had a very good sit down with Jason. He answered all of my questions and is taking a look at the 530 screen.

 

[TMetzinger]

Mine just started rotating with no flags at all. It was on my instrument checkride, too, during the single-engine approach. I never did learn what the actual failure was, but I vaguely remember being told it was a mechanical issue, not an electric or vacuum problem.

 

[wsuffa]

My King HSI system failed by locking on a heading about 40 degrees off of the wet compass heading. Outbound from Four Corners toward the mountains. No flags. No smoke. Got it working right for that flight by manually slaving it, then once on heading turning auto-slave back on. I was headed home, and took it to the shop once I got there.

Shop found that someone had apparently swapped my 4-5 year old KCS-55 remote compass with a old "hacked" one filled with improper parts. We had to overhaul the unit and it's been fine.